Method for generating a voice announcement as feedback to a handwritten user input, corresponding control device, and motor vehicle

ABSTRACT

A method for generating a voice announcement as feedback to a handwritten user input is disclosed in which a user enters on a control device. A list of possible whole words which can be entered by the user input is provided together with a corresponding transcription and a predetermined word end, which comprises one or more characters of a whole word of the whole words, is removed from the end of said whole word in accordance with a predetermined shortening rule and corresponding to this, a transcription end corresponding to the word end is determined based on a predetermined assignment rule and is removed from the corresponding transcription of the whole word for generating a partial word and an associated partial transcription. The partial word and the partial transcription are added to another list.

TECHNICAL FIELD

The present disclosure relates to a method for generating a voicemessage as feedback to a handwritten user input that a user enters on acontrol device. The present disclosure also includes said control deviceand a motor vehicle comprising such a control device.

BACKGROUND

In a motor vehicle or another device, for example a smartphone or atablet PC, an input apparatus can be provided, by means of which a usercan enter a handwritten user input. Such a handwritten user input may behandwritten text or a handwritten word, for example. So that the usercan check or recognize whether their handwritten user input wascorrectly recognized by the control device, it may be provided that ahandwritten input word can first be recognized in the known manner bymeans of handwriting recognition software, as a result of which the wordis present as alphabetic-character text, and then the recognized word isoutput as a voice message using speech synthesis (TTS—text to speech).The user then receives verbal or acoustic feedback and can use it tocheck whether their handwritten user input was correctly recognized.

If, for example, a user in a motor vehicle would like to enter the word“Berlin” as the destination address in a navigation assistance system,they can do this, among other things, via a touchscreen. To this end,they can carry out the handwritten user input by writing on thetouchscreen with a finger or an input object (for example a stylus).This handwritten user input can then be output acoustically as a voicemessage by means of a voice synthesis apparatus and can thus beconfirmed. This can be done either by spelling the user input (in theexample, “B E R L I N”) or by reading it out as a whole word.

A voice message by means of spelling is cognitively potentially lessfavorable for a user because they can lose their bearings with a longerword. There is therefore in particular the need to distract a driver aslittle as possible while they are driving a motor vehicle, by theconfirmation or voice message for the handwritten user input being madein a natural form, i.e., as a whole word that is read out (in theexample, “Berlin”).

However, the problem arises here that a user can interrupt thehandwritten user input by taking an input break. For example, they canpause or stop while writing a word. While driving a motor vehicle, thismay be necessary in order to carry out a driving maneuver, for example.There is then an incomplete handwritten user input in which there is anincompletely written word, for example “Berl” for the word “Berlin.” Theproblem that can arise here is that an aural or phonetic transcriptionis always required for the voice message of a word, which specifieswhich sound sequences are to be output by the voice message in order toreproduce the relevant word aurally or linguistically. Transcription ofthis kind can be based on a phonetic alphabet or a phonetictranscription. One example is the International Phonetic Alphabet (IPA).For complete words, for example in the case of place names, a databaseof a navigation system can be used, from which the transcription forstreet names and/or place names can be taken. In the above example, aphonetic transcription for the whole word “Berlin” is available. Therecognized, handwritten word is searched for in such a database and thetranscription for the word is then read out from the database. However,if there is only a partially written word, i.e., a partial word, thedatabase search will not be successful, as there is no database entryfor this partial word. A partial address therefore cannot be resolvedbecause the whole word as entered in the database is missing. The samecan also happen for an address entry made up of several words (e.g.“Champs Elysees”) if the handwritten user entry initially only specifiesone of the words. This can lead to an ambiguous search result in thedatabase.

In addition, searching such a database is very computationallyintensive, which is why a repeated search for each partial entry or eachentered partial word (for example, after each newly entered letter)would cause a computing load in the navigation database that isundesirable.

DE 10 2012 217 160 A1 describes a speech synthesis system which isdesigned to determine suitable sounds during speech synthesis. Theoutput quality can be iteratively improved. In this case, in a synthesismachine, speech units of spoken language that have already been recordedare drawn upon. In order to correctly pronounce the partial word or toeven make it possible to find, a corresponding number of voicerecordings would have to be available, in the example, not only of“Berlin” but also of “Berl.” This would require a lot of data storage.

An audio reproduction of written documents is known from DE 600 12 655T2. This audio playback also uses ready-made audio snippets to generatethe speech and generates new audio snippets if no suitable audio snippetis found. For this purpose, a word to be pronounced is broken down intocomponents of its phonemes and the most likely pronunciation is thendetermined on the basis of a probability analysis. This can result in anerror.

A method for outputting information from vehicle operating instructionsis known from DE 10 2012 006 714 A1. The instruction manual can beconverted into speech in order to operate a text-to-speech facility.However, only a completely written operating manual can be output as avoice message in this case.

A method for entering characters into a data-processing system is knownfrom DE 10 2005 021 526 A1. Using a sensor apparatus a plurality ofhandwriting elements are detected one after the other, each of whichrepresents a sentence consisting of at least one character. Using arecognition apparatus, the respective sets of characters are determinedfrom the detected handwriting elements in order to use the determinedsets of characters to form a character sequence in the sequence in whichthe handwriting elements assigned to the sentences were detected. Anacoustic output apparatus outputs the determined sets of characters inthe order in which the handwriting elements assigned to the sentenceswere detected.

A method for providing clues for handwriting recognition is known fromUS 2006/0210173 A1. The clues can be associated with a database of knownvalues or expected character types. They minimize the list of possibletext values of fields that recognition devices use to recognizehandwriting, such that fewer opportunities have to be checked for amatch and the probability of accurate recognition increases.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

FIG. 1 shows a plan view of a schematic trajectory of a vehicle, inaccordance with some embodiments.

DETAILED DESCRIPTION

The problem addressed by the present disclosure is to make it possibleto generate a voice message as feedback even if the handwritten userinput by a user to be output only contains a partial word, i.e., not afully written word or a whole word.

The problem is solved by the subject matter of the independent claims.Advantageous embodiments are described by the dependent claims, thefollowing description, and the drawings.

In some embodiments, a method for generating a voice message as feedbackto a handwritten user input is disclosed. The user enters the user inputon a control device. In the manner described, the problem can now arisethat the user input does not indicate a whole word, but only a partialword, because the user is taking a break in input, for example, i.e.,interrupting their handwritten user input. Nevertheless, a voice messageshould be possible for the partial word entered up to then. For thispurpose, according to the method, a list of possible whole words thatcan be entered by the user input, i.e., complete words, is providedtogether with the relevant aural or phonetic transcription. Thetranscription describes what sound sequence is to be generated in thevoice message in order to reproduce the whole word verbally oracoustically. In the case of one or some or each of the whole words thatcan be entered, a predetermined word end is then removed from its endonce or repeatedly in accordance with a predetermined abbreviation rule.The word end can thus comprise a letter or a sequence of letters. Theword end is thus cut off or removed from the whole word from the back orfrom the end. The word end comprises one or more characters of the wholeword, such that the whole word is shortened by the word end. Thiscreates a new partial word, namely the whole word shortened by the wordend. The question is then how to pronounce this abbreviated whole word,i.e., the now incomplete whole word. Accordingly, a transcription endcorresponding to the removed word end is determined corresponding to therelevant abbreviated whole word by means of a predetermined assignmentrule and is removed from the corresponding transcription of the wholeword, which means that, each time, not only a partial word (i.e., awhole word from which a relevant word end has been removed once ormultiple times) but also an associated partial transcription (completetranscription from which the transcription end corresponding to theremoved word end has been removed once or multiple times) are thereforegenerated. The partial word thus generated and the associated partialtranscription are added to said list. The list is thereforeautomatically supplemented with partial words (incomplete words) and anassociated transcription.

Therefore, according to the method described herein in accordance withsome embodiments, a voice message can also be generated as feedback to ahandwritten user input which only comprises a partially written wholeword, i.e., a partial word. A corresponding partial transcription isthen available in the list. In addition, the search for the partial wordin the list is successful since there is an explicit or separate entryfor the partial word in the list.

Accordingly, a voice message is provided as feedback even for anincomplete handwritten user input, i.e., only partially written wholeword.

In some embodiments, while the user has only partially entered one ofthe whole words by means of the user input such that one of the partialwords is entered, the associated partial transcription is sought fromthe list depending on the entered partial word and the voice message forthe partial word is generated on the basis of the partial transcription.The partial word and its partial transcription therefore do not need tohave been explicitly entered in the list for the voice message, forexample, by an operator, but instead a list of the whole words and theirtranscription is sufficient here. The method automatically supplementsthe list with the partial words and their correct partial transcriptionin the manner described, and this partial transcription is then used forthe voice message.

In some embodiments, a letter-by-letter abbreviation of the relevantword is brought about by means of the abbreviation rule. Therefore,there are as many partial words as the whole word has letters, whichthen corresponds to all the possibilities that a user can possiblygenerate when entering a partial word by hand. A voice message is thusmade possible for each state of the handwritten user input during awhole word.

In some embodiments, a corresponding transcription character or acorresponding transcription character sequence is assigned by means ofsaid assignment rule (finding the corresponding transcription end at aword end) for some or all characters from which the possible whole wordsare formed. This is necessary because each individual letter does nothave to correspond exactly to a single transcription character. For eachletter removed at the end of the whole word, which can be removed onceor multiple times), the associated transcription character or acorresponding transcription character sequence is assigned and this isthen removed from the corresponding transcription as the transcriptionend. This has the advantage that a correct partial transcription isachieved even if the associated transcription provides severaltranscription characters for a single letter of the whole word. This maybe the case for the letter “b,” for example, which can be represented ina transcription by the transcription character “2b.” In addition, it canalso be recognized on the basis of a context whether a transcriptioncharacter is to be removed at all, such that in this embodiment it canbe provided that no transcription character is assigned by means of theassignment rule. For example, the letter sequence “tt” is represented bythe transcription character sequence “.t.” If a “t” is then removed byabbreviating by a letter so that “t” remains, the transcriptioncharacter sequence “.t” must not be removed as well since it stillrepresents the remaining character “t.” The assignment rule can thusadvantageously represent or take into account linguisticcharacteristics.

In some embodiments, said list is provided as an independent look-uptable (LUT) in a memory of the control device. Accordingly, a search forpartial words and their partial transcriptions can be carried outindependently of a database in which the originally provided list isstored. This prevents a strain from being placed on the database duringoperation of the control device. A look-up table for a list, whichprovides an assignment of whole words and partial words to acorresponding transcription and partial transcription, can beimplemented with a smaller data volume than the navigation database 24from which the original list was taken, such that a correspondingly fastand/or low-resource search is possible.

In some embodiments, the list of possible whole words is extracted froma navigation database. In this way, a voice message can be produced fordatabase entries in a navigation database. In this case, the method isthen used to automate the completion of the possible partial words thatmay arise from a handwritten user input due to an input interruption oran input pause.

The use of the method according to various embodiments described hereinin a control device in a motor vehicle is particularly advantageous. Inaccordance with some embodiments, the control device disclosed herein isoperated in a motor vehicle. A handwritten user input can lead to aninput pause here because a user of the motor vehicle has to concentrateon road traffic, for example, and therefore pauses input.

In some embodiments, a control device includes an input apparatus forreceiving handwritten user input, an output apparatus for outputting avoice message, and a processor apparatus. The handwritten user input canbe received by the input apparatus, for example, via a touchpad or atouchscreen. An output apparatus for outputting the voice message canfor example be based on a TTS system known per se from the prior art.The processor apparatus is configured to implement an embodiment of themethod according to the invention. For this purpose, the processorapparatus may comprise at least one microcontroller and/or at least onemicroprocessor. The processor apparatus may have a program code, whichcontains program instructions which are configured to implement theembodiment of the method according to the invention when executed by theprocessor apparatus. The program code may be stored in a data memory ofthe processor apparatus.

In some embodiments, the control apparatus is configured to recognize aninput pause during the user input. This can be implemented, for example,by it being recognized that a change in the user input, i.e., a changein a line drawn by the user, for example, remains unchanged for apredetermined minimum duration (for example in a range of from 0.5seconds to 5 seconds) and/or a force acting on the input apparatusbecomes less than a predetermined threshold value. Furthermore, thecontrol device is configured to output a partial word that has beenreceived via the input apparatus up to that point as a voice message bymeans of the output apparatus when an input pause is recognized. Thepartial transcription of the partial word required for this can beprovided in the manner described in the list supplemented with thepartial words and their partial transcription.

In some embodiments, a motor vehicle, which comprises an embodiment ofthe control device according to some embodiments as disclosed herein isdescribed. The motor vehicle may be designed as a car, in particular asa passenger car or truck. In the manner described, there is a highprobability of an input pause in a handwritten user input, particularlyin a motor vehicle. The implementation of the method as described hereinin accordance with some embodiments is therefore particularlyadvantageous here.

The features of the described embodiments may also be combined.

The embodiments explained below are preferred embodiments of thedisclosure and described using FIG. 1. In the embodiments, the describedcomponents of the embodiments each represent individual features, whichare to be considered to be independent of one another and in othercombinations of the features. In addition, the embodiments described mayalso be supplemented with further features already been described in thepresent disclosure.

In the FIGURE, the same reference signs designate elements that have thesame function.

FIG. 1 schematically shows a motor vehicle 10, which may for example bea motor vehicle, in particular a passenger car or truck. Instead of themotor vehicle 10, however, another device, for example a smartphone or atablet PC, can also be provided. In the following, a motor vehicle istaken as a starting point merely for the sake of clarity.

An input apparatus 11 for entering or receiving a handwritten user input12 can be provided in the motor vehicle 10. A handwriting-recognitionapparatus 13 (HWR) can recognize an entered word 14 on the basis of theuser input 12. The word 14 can be a whole word or, as shown in theFIGURE, an entered partial word 15. The partial word “Berl” shown as anexample may be the start of the whole word “Berlin.” In general, a wholeword is a complete word, and a partial word is an incomplete word. Itmay be provided that when an input pause is recognized, if the userinterrupts their user input on the input apparatus 11, e.g. for apredetermined minimum duration, the already entered partial word 15 isstill output to the user by means of an output apparatus 16 as a voicemessage 17, e.g. by means of a speaker apparatus 18 of the outputapparatus 16, such that they can hear what they have written so far orwhat has been recognized so far. The conversion into the voice message17 can take place in a manner known per se by means of a voice synthesissystem 19 (TTS system).

The speech synthesis system 19, however, requires a phonetictranscription 20, which describes the sound sequence which therecognized word 14 represents, in order to generate the voice message17. In the case of a partial word 15, a transcription 20 is necessary,which is referred to here as a partial transcription 21 because itrelates to the transcription of a partial word, i.e., an incompleteword. The speech synthesis system 19 can additionally or alternativelybe configured to determine the transcriptions of the whole words 23itself. This is known, for example, when the aim is to output messages(news) or SMS messages (SMS—short message service) via voice output. Adisadvantage, however, is that this internal generation of thetranscription is generally worse/less precise than if an existingtranscription from outside (navigation database) is used. Therefore, themethod also serves the purpose of having the TTS produce the bestpossible quality.

In order to obtain this partial transcription, the following isprovided:

A list 22 of the whole words 23 that can be entered by the user can betaken from a navigation database 24 (NavDB), for example. An associatedtranscription 25, i.e., a whole-word transcription, can also be takenfrom this navigation database 24 for each whole word 23, such that thelist 22 includes a transcription 25 for each whole word 23. The list 22can contain more than the three whole words shown, as is symbolized byellipses 26 (“ . . . ”).

The following can then be provided for each or some or one whole word23. This is illustrated in the FIGURE using the example of the wholeword “Berlin.” A predetermined word end 28 can be removed in successionfrom a word end 27 of the whole word 23. The sequence of word ends 28may correspond, for example, to abbreviating the whole word 23 letter byletter. The transcription 25 belonging or assigned to the whole word 23then also has to be abbreviated. However, an individual transcriptioncharacter of the transcription 25 does not correspond to every letter ofthe whole word 23. An assignment rule 29 can therefore be provided whichassigns a corresponding transcription character or a correspondingtranscription character sequence S (for example “i:”) to each letter orgenerally to each possible word end C.

From the transcription 25 of the whole word 23, a correspondingtranscription end 31′ can then be formed from the assignment rule 29 inaccordance with the removed word end 28 and can be removed from thetranscription 25. This results in an associated partial transcription25′ for the remaining partial word 28′. When removing word ends 28, witheach step of removing the whole word 23 can be taken as a starting pointagain and this can be shortened by an increasingly long word end (asshown in the FIGURE), or the preceding step can be taken as a startingpoint with each step of removal from the partial word 28′. Bothapproaches are equivalent.

This can be stored together with the possible whole words 23 in anextended list 30, which can be designed as a look-up table (LUT) and canbe stored in a memory 31 of the control device B.

A control device B can be provided in the motor vehicle 10, by means ofwhich a user can carry out a handwritten user input 12, for example forentering a navigation destination in a navigation system or a navigationassistance system.

If the user input 12 is then received and the recognized word 14 ispresent, a check can be made for the voice message 17 in the expandedlist 30 as to whether the recognized partial word 15 is containedtherein. If the search result 32 is negative, the partial word 15 can beoutput as a spelling 33 by means of the speech synthesis of the speechsynthesis system 19. If the search result 32′ is successful, i.e., ifthe partial word 15 is recognized in the list 30, the associated partialtranscription 21 can be read out from the list 30 and made available tothe speech synthesis system 19. This can then generate the voice message17 on the basis of the partial transcription 21. The user thereforehears the partial word 15 that has been written or entered so far whenthey pause in their input.

A particularly preferred embodiment in connection with a motor vehicle10 and a navigation database 24 is described below.

The TTS system (speech synthesis system 19) is therefore linked to alook-up table LUT, which contains all possible orthographic variants ofstreet and place names as a key, and the corresponding transcriptions ofthese variations, i.e., the partial transcriptions 21, as values.

The (whole-word) orthographies and transcriptions are extracted inadvance from the navigation database 24 and stored in the look-up tableLUT. This LUT can then be coupled to the TTS system during runtime.Moving the data relevant for the TTS (words and transcriptions) from thenavigation database 24 to a separate TTS resource (list 30) eliminatesthe problem of access time.

However, a direct transfer of the information from the navigationdatabase 24 would not solve the problem of pronunciations in the eventof incomplete address entries such as “Frankfu” (for Frankfurt) or“chaus” (for Chaussee).

Therefore, the orthographies and transcriptions from the navigationdatabase 24 are further processed.

Using a heuristic algorithm (assignment rule 29), it is possible tobreak down the orthographies synchronously with the associatedtranscriptions into individual parts or partial words 28′. This can bedone on a syllable basis or on a character basis, for example.

This breakdown of the orthographies and transcriptions lastly takesplace for all entries in the navigation database 24. The results arerecorded in the LUT, i.e., the supplemented list 30, and are thenavailable for high-performance retrieval by the TTS system.

By means of this method, correct acoustic confirmation can be achievedfor each partial-word input by a user in the area of address input, e.g.by means of a touchscreen. Owing to the close connection of the LUT, theunderlying data is available for use almost without delay. Inparticular, incomplete entries can be handled reliably using the method,since a phonetic transcription is stored in the LUT for all variants.

The breakdown takes place on the basis of the heuristic algorithm, as isimplemented by the assignment rule 29, and can take various forms.Useful options are, for example, breakdown on a syllable basis or on acharacter basis as an abbreviation rule.

Using the example of the whole word “Westerbüttel,” the abbreviationusing the “letter-by-letter” abbreviation rule may look as follows:

Orthography Transcription Westerbüttel ′vEs.t$R.′2bY.t$l Westerbütte′vEs.t$R.′2bY.t$ Westerbütt ′vEs.t$R.′2bY.t Westerbüt ′vEs.t$R.′2bY.tWesterbü ′vEs.t$R.′2bY Westerb ′vEs.t$R.′2b Wester ′vEs.t$R Weste′vEs.t$ West ′vEs.t Wes ′vEs We ′vE

Only the first whole-word entry “Westerbüttel” with its transcription“‘vEs.t$R.’2bY.t$1” can be extracted from the navigation database 24.All further entries are then generated by the algorithm. In the variantshown, the place “Westerbüttel” is abbreviated backwards by onecharacter or letter each time. The same abbreviation is carried outduring the transcription.

However, 1:1 abbreviation is not always possible here. For example, thetranscription for “Holzchaussee” is as follows: “‘hOlt&s.SO.’2se:.” Thetranscription of the letter “z” alone is provided here by “t&s.”Similarly, in this example, the combinations “ch”<->“S” and “au”<->“O”would be difficult and have to be processed accordingly by thealgorithm.

The application is basically applicable to all phonetic alphabets, butrequires adjustments in the heuristics (assignment rule 29).

Overall, the examples show how to provide partial transcriptions toincrease the quality of TTS synthesis (TTS—text-to-speech) in the fieldof handwriting recognition.

1.-10. (canceled)
 11. A method for generating a voice message asfeedback to a handwritten user input entered by a user on a controldevice, the method comprising: receiving a first list comprising aplurality of whole words together with a corresponding phonetictranscription, wherein the plurality of whole words comprises a wholeword received as handwritten user input; removing from the whole word ofthe plurality of whole words a predetermined word end according to apredetermined abbreviation rule, the predetermined word end comprisingone or more characters of the whole word; determining a transcriptionend corresponding to the removed word end from a transcriptioncorresponding to the whole word according to a predetermined assignmentrule; generating a partial word corresponding to the whole word, and apartial transcription corresponding to the partial word by removing thedetermined transcription end from the transcription corresponding to thewhole word; and adding the partial word and the partial transcriptioncorresponding to the partial word to a second list.
 12. The method ofclaim 11, further comprising: receiving a partially entered wordcorresponding one of the plurality of whole words; and retrieving, fromthe second list, a partial transcription corresponding to the receivedpartially entered word; and generating the voice message correspondingto the received partially entered based on the partial transcriptioncorresponding to the received partially entered word.
 13. The method ofclaim 11, wherein the abbreviation rule comprises a letter-by-letterabbreviation of a word of the plurality of words.
 14. The method ofclaim 11, wherein a transcription character or a transcription charactersequence or no transcription character is assigned corresponding to theassignment rule for some or all characters of the whole word.
 15. Themethod of claim 11, wherein the second list is provided as anindependent look-up table (LUT) in a memory of the control device. 16.The method of claim 15, wherein the control device is operated in amotor vehicle.
 17. The method of claim 11, wherein the first list isextracted from a navigation database.
 18. The method of claim 11,further comprising: detecting an input pause in the handwritten userinput; and in response to the detection of the input pause, generating avoice message corresponding to a partial word received up to the inputpause.
 19. A control device, comprising: an input apparatus configuredfor receiving a handwritten user input; an output apparatus configuredfor outputting a voice message; and a processor configured to performoperations comprising: receiving a first list comprising a plurality ofwhole words together with a corresponding phonetic transcription,wherein the plurality of whole words comprises a whole word received ashandwritten user input, and wherein the first list is extracted from anavigation database; removing from the whole word of the plurality ofwhole words a predetermined word end according to a predeterminedabbreviation rule, the predetermined word end comprising one or morecharacters of the whole word; determining a transcription endcorresponding to the removed word end from a transcription correspondingto the whole word according to a predetermined assignment rule;generating a partial word corresponding to the whole word, and a partialtranscription corresponding to the partial word by removing thedetermined transcription end from the transcription corresponding to thewhole word; and adding the partial word and the partial transcriptioncorresponding to the partial word to a second list.
 20. The controldevice of claim 19, wherein the processor is further configured toperform the operations comprising: detecting an input pause in thehandwritten user input; and in response to the detection of the inputpause, generating a voice message corresponding to a partial wordreceived up to the input pause.
 21. A motor vehicle, comprising: acontrol device, comprising: an input apparatus configured for receivinga handwritten user input; an output apparatus configured for outputtinga voice message; and a processor configured to perform operationscomprising: receiving a first list comprising a plurality of whole wordstogether with a corresponding phonetic transcription, wherein theplurality of whole words comprises a whole word received as handwrittenuser input, and wherein the first list is extracted from a navigationdatabase; removing from the whole word of the plurality of whole words apredetermined word end according to a predetermined abbreviation rule,the predetermined word end comprising one or more characters of thewhole word; determining a transcription end corresponding to the removedword end from a transcription corresponding to the whole word accordingto a predetermined assignment rule; generating a partial wordcorresponding to the whole word, and a partial transcriptioncorresponding to the partial word by removing the determinedtranscription end from the transcription corresponding to the wholeword; and adding the partial word and the partial transcriptioncorresponding to the partial word to a second list.
 22. The motorvehicle of claim 21, wherein the processor is further configured toperform the operations comprising: detecting an input pause in thehandwritten user input; and in response to the detection of the inputpause, generating a voice message corresponding to a partial wordreceived up to the input pause.